The present invention relates generally to a tape cassette loading system of a recording and/or reproducing apparatus such as a video tape recorder (VTR). More specifically, the invention relates to an improved loading mechanism in which the amount of unused space is decreased thus allowing the overall size of the recording and/or reproducing apparatus to be reduced.
VTR and digital recording type PCM recorders generally comprise a rotary head which rotates diagonally relative to the traveling direction of the magnetic tape and thereby records information in diagonal tracks on the magnetic tape. The helical wrapping of the magnetic tape about the head drum requires a special loading system.
In conventional tape cassette loading systems, a so-called M type loading system and a so-called U type loading system are known. In the U type loading system, the axis of the rotary head drum is at essentially right angles to the mechanical chassis. Tape guiding posts, for withdrawing the magnetic tape from the tape cassette case and guiding it towards the rotary head drum, are provided at a tape supply reel side and a take-up reel side respectively. One of these guiding posts moves around the rotary head drum parallel to the plane of the chassis, while the other guiding post moves upwardly or downwardly around the head drum so as to wrap the tape helically thereabout. On the other hand, in the M type loading system, the rotary head drum is diagonally mounted on the mechanical chassis, and the tape guiding posts are arranged vertically on the mechanical chassis. The inclination of axis of the rotary head drum to that of the tape guiding posts permits the helical wrapping of the tape about at least a portion of the periphery of drum.
In recent years, the overall size and thickness of a portable VTR camera has decreased. When miniaturizing the conventional VTR cameras, the following objects are encountered.
The rotary head drum takes up a relatively great deal of space. Therefore, a cassette loading system in which the rotary head drum is partially received into the tape access portion of a magnetic tape cassette case is sought. The relatively greater height of the rotary head drum of the M-type loading due to its inclination does not permit the head drum to be easily received in the access portion of the tape cassette. On the other hand, in the U type loading system wherein the rotary head drum is mounted at right angles to a mechanical chassis, only one tape guiding post provided at either the supply reel side or the take-up reel side moves upwardly or downwardly relative to the rotary head drum so as to wrap the magnetic tape helically thereabout. Therefore, the height of the rotary head drum is relatively great relative to that of the tape access portion of the tape cassette case and therefore the portion of the drum that is not received within tape cassette's access portion remains relatively large.